<!doctype html>
<html lang="zh-cn">

<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>404</title>
    <style>
        *,
        *::before,
        *::after {
            box-sizing: border-box
        }

        body {
            margin: 0;
            padding: 0;
            min-height: 100vh;
            display: flex;
            justify-content: center;
            align-items: center;
            font-family: Arial, sans-serif;
            font-size: 1rem;
            line-height: 1.5;
            color: #212529;
            text-align: left;
            background: #fcfcfc;
        }
        .flex-flow {
            flex-flow: column;
        }
        h1 {
            display: block;
            font-size: 1.5rem;
            font-weight: 500;
        }
    </style>
</head>

<body>
    <div class="flex-flow">
        <h1>404</h1>
        <p>页面不存在。</p>
    </div>

</body>

</html>